Taiwanese media has reported that fisherman Tsai Po, 54, was made to kneel on the floor for four hours and was not even given water to drink.

In an interview with ANC, Manila Economic and Cultural Office (MECO) Chairman Amadeo Perez said he has already spoken to Taiwanese authorities about the incident.

"We sent them an official copy of the report of [Bureau of Fisheries and Aquatic Resources] showing the evidence that the fisherman was really fishing in our territorial boundaries. And the picture shows that he was in good health and well-taken cared of," Perez said.

He added that Philippine National Police (PNP) chief Director General Alan Purisima has already instructed the police director of Batanes "to treat the fisherman very well."

"I hope Taiwan will understand that the policemen and the bantay dagat people were just doing their duty in consonance with our laws," he said.

The arrested fisherman is to be charged with poaching, which is punishable by a US $100,000 fine, confiscation of his catch, fishing equipment and fishing vessel, provincial police officer Victor de Sagon told AFP on Thursday.

The incident comes as the two countries seek to mend ties after the fatal shooting of another Taiwanese fisherman back in May.

The National Bureau of Investigation (NBI) has since said Philippine Coast Guard personnel used excessive force and tampered with evidence. -- With report from ANC; Agence France-Presse